US3964315A - Apparatus including novel bridge circuit - Google Patents

Apparatus including novel bridge circuit Download PDF

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Publication number
US3964315A
US3964315A US05/432,778 US43277874A US3964315A US 3964315 A US3964315 A US 3964315A US 43277874 A US43277874 A US 43277874A US 3964315 A US3964315 A US 3964315A
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United States
Prior art keywords
resistor
junction
junctions
capacitor
joined
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US05/432,778
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English (en)
Inventor
John S. Engelhardt
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Ericsson Inc
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Anaconda Co
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Publication date
Application filed by Anaconda Co filed Critical Anaconda Co
Priority to US05/432,778 priority Critical patent/US3964315A/en
Priority to IT70522/74A priority patent/IT1024973B/it
Priority to CA215,290A priority patent/CA1010954A/en
Priority to JP49149121A priority patent/JPS50104066A/ja
Priority to GB849/75A priority patent/GB1490261A/en
Priority to DE19752500805 priority patent/DE2500805A1/de
Priority to FR7500704A priority patent/FR2257908B1/fr
Application granted granted Critical
Publication of US3964315A publication Critical patent/US3964315A/en
Assigned to ANACONDA-ERICSSON INC., A CORP. OF reassignment ANACONDA-ERICSSON INC., A CORP. OF ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ANACONDA COMPANY, THE A CORP. OF DE
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R17/00—Measuring arrangements involving comparison with a reference value, e.g. bridge
    • G01R17/10—AC or DC measuring bridges

Definitions

  • the resistors have been adjusted to read null at a pilot wire temperature of zero degrees Celsius, and the degree of unbalance, indicative of the pilot wire resistance, and thus its temperature, is determined from the scale reading of a milliameter.
  • the apparatus of the above-named patents has found its principle application in monitoring three-phase A.C. cables and in this service it has been found that where a pilot wire is incorporated in the conductor of one of the phases, currents induced in it from the other two phase conductors interfere seriously with the bridge readings, and particularly with the operation of any voltage controlled oscillator and amplifier that may be used for radio transmission of the bridge measurements.
  • I have invented an apparatus for measuring the D.C. resistance of a resistive element carrying an A.C. current component comprising first, second, third, fourth and fifth conductor junctions in which the element is joined to the first and second junction and a first resistor and first capacitor are joined, in series, to the first and fifth junction.
  • My apparatus also comprises a second resistor and second capacitor joined, in parallel, to the second and fifth junction, a third resistor and third capacitor joined, in series, to the second and fourth junction, a fourth resistor joined to the third and fourth junction and a fifth resistor joined to the first and fourth junction.
  • a fourth capacitor is joined to the fourth and either the third or first junction in parallel with the fourth or fifth resistor.
  • My apparatus also comprises a sixth resistor joined to the second and third junction, a D.C. power supply joined to the first and third junction and a potential measuring means joined to the fifth and fourth junction so that the first, second, third and fourth junctions form the terminal points of a D.C. bridge for measuring the resistance of the element and the first, second, fourth and fifth junctions form the terminal points of an A.C. bridge for balancing out A.C. current components.
  • the fourth capacitor will be joined parallel to the fourth resistor and a fifth capacitor will be joined to the first and fourth junction, parallel to the fifth resistor.
  • the first, third and sixth resistors may be variable, a capacitor may join the first and second junction in parallel with the resistive element being measured, and it may comprise a resistor between the fourth and fifth junction in series with the measuring means.
  • the measuring means may, advantageously, comprise indicator means responsive to the magnitude of the element resistance and a voltage controlled oscillator responsive to the voltage across the fourth and fifth junction.
  • I have invented an apparatus for measuring the D.C. resistance of a resistive element carrying an A.C. current component comprising a D.C. bridge circuit with four impedance legs and four junctions joining the legs, and having the element included in one of the legs.
  • a D.C. power supply joins two of the junctions and a potential measuring means joins another two of the four junctions.
  • My apparatus also comprises an A.C. bridge circuit comprising four impedance legs and four junctions joining them; with three of the junctions of the A.C. circuit being in common with three of the junctions of the D.C. circuit.
  • One of the legs of the A.C. circuit that joins one of these common junctions is joined, in series with the measuring means, to another of the common junctions.
  • the element being measured is in thermal contact with a high voltage cable conductor and the apparatus provides means for measuring the conductor temperature while the whole circuit has assumed the high conductor potential and is insulated from ground.
  • FIG. 1 shows a circuit diagram of my invention.
  • FIG. 2 shows the D.C. equivalent of the circuit of FIG. 1.
  • FIG. 3 shows the A.C. equivalent of the circuit of FIG. 1.
  • FIG. 1 the circuit of my apparatus is indicated generally by the numeral 10 with five junctions 11, 12, 13, 14, 15. It will be understood that the numerals 11-15 refer to electrical junctions each of which may, in the usual manner comprise a plurality of connectors with negligble impedance between them.
  • An element 16 whose resistance is to be measured joins the junctions 11, 12 in parallel with a capacitor 17.
  • the element 16 comprises a pilot wire that has been embedded in a high voltage cable conductor in series with the cable conductor itself which thus forms a portion of the element 16.
  • a twin pilot wire within the scope of the present invention in which case the cable conductor itself would not constitute the return lead.
  • A.C. voltage drop which may have a magnitude of 10 volts per thousand amperes must be vectorially added to the induced voltage whose effects are compensated in the present invention. This voltage drop is not shown separately in FIG. 3, but is considered, where applicable, to be included in the alternating voltage symbol.
  • a resistor 18 made up of fixed and variable segments 19, 21 joins the junction 12 to the junction 13 in parallel with a capacitor 22. In operation the resistor 18 is adjusted to match the resistance of the element 16 at 0°C.
  • a 1000-ohm resistor 24 joins the junctions 13, 14 in parallel with a capacitor 26 and a 1000 ohm resistor 27 joins the junctions 14, 11 in parallel with a capacitor 28.
  • the resistors 24, 27 form two legs of a D.C. bridge.
  • the capacitors 26, 28 have a total capacitance of 5.3 microfarads, and although I have found it convenient to employ two capacitors of 2.65 microfarads capacitance for this purpose it is only important, as shall be more fully explained hereinbelow, that the two capacitors, in parallel, should have a specified value, and this can be made up by any convenient combination including the complete omission of one of the capacitors 26 or 28.
  • a 12 volt D.C. power supply 29 is applied across the junctions 11, 13. As has been explained in the patents included hereinabove by reference this supply is conveniently induced, rectified, and regulated from the power cable itself.
  • a 50 ohm variable resistor 31 in series with a 53 microfarad capacitor 32 joins the junctions 11 and 15, and a 100 ohm resistor 33 in parallel with a 26.5 microfarad capacitor 34 joins the junctions 12 and 15.
  • a variable resistor 36 is inserted in series with the meter 23 merely for the adjustment of the latter.
  • a radio signal can be broadcast and for this purpose the potential between the junctions 15 and 14 can be sensed by a voltage controlled oscillator 37 tapping a potentiometer 38 in cooperation with an amplifier-transmitter 39 and antenna 41.
  • a 250 ohm resistor 43 which may be variable, in series with a capacitor 44, joins the junctions 12 and 14.
  • FIGS. 2 and 3 representing D.C. and A.C. equivalents of the circuit of FIG. 1, have been added to the drawing. From FIG. 2 it will be seen that the apparatus of FIG. 1 functions for D.C. measurement of the resistance of the element 16 as a Wheatstone type bridge wherein the meter is calibrated to indicate the desired readings rather than a mere null joint.
  • the resistors 31, 43 which are in series with the respective capacitors 32, 44 do not affect this D.C. circuit.
  • the voltage controlled oscillator 37, and resistor 38 are, of course, applicable to this circuit, although they have been omitted from FIG. 2 for clarity. As shown in FIG. 3 the opposing junctions 12, 11 and 15, 14 form an A.C.
  • the resistor 24 and capacitor 26 then effectively parallel the resistor 27 and capacitor 28 in joining the junctions 11 and 14.
  • the junctions 11, 12, and 14 are seen to be common to the D.C. equivalent bridge circuit of FIG. 2 and the A.C. equivalent bridge circuit of FIG. 3.
  • the leg of the A.C. bridge that includes the resistor 33 is connected in series with the meter 23 (in FIG. 2) between the junctions 12 and 14 which are common to both circuits.
  • the resistors 24, 27 and capacitors 26, 28 are shown in FIG. 3 by the equivalent 500 ohm resistor 46 and 5.3 microfarad capacitor 47.
  • the capacitors 32, 44 which were necessary to exclude the resistors 43, 31 from the D.C. circuit are balanced by including capacitors 17, 34 in the A.C. bridge, the voltage supply of which is shown symbolically as an A.C. component in the element 16. Since, in operation, the components forming the bridge of FIG. 3, once they have been adjusted for a null reading of a meter 48 will need no further adjustments even though the apparatus may be employed with different sizes and lengths of cable, this meter is conveniently not the same meter as the one that will be installed for measuring the cable temperatures on the D.C. bridge, and an oscilloscope can be used for the meter 48, adjusting resistors 31 and 43 to adjust the impedance for a null reading.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
  • Measurement Of Resistance Or Impedance (AREA)
  • Measuring Temperature Or Quantity Of Heat (AREA)
US05/432,778 1974-01-11 1974-01-11 Apparatus including novel bridge circuit Expired - Lifetime US3964315A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US05/432,778 US3964315A (en) 1974-01-11 1974-01-11 Apparatus including novel bridge circuit
IT70522/74A IT1024973B (it) 1974-01-11 1974-12-04 Circuito a ponte particolarmente per la misura della temperatura dei conduttori di un cavo ad alta tensione
CA215,290A CA1010954A (en) 1974-01-11 1974-12-05 Apparatus including novel bridge circuit
JP49149121A JPS50104066A (enrdf_load_stackoverflow) 1974-01-11 1974-12-27
GB849/75A GB1490261A (en) 1974-01-11 1975-01-08 Resistance measuring apparatus
DE19752500805 DE2500805A1 (de) 1974-01-11 1975-01-10 Brueckenschaltung
FR7500704A FR2257908B1 (enrdf_load_stackoverflow) 1974-01-11 1975-01-10

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US05/432,778 US3964315A (en) 1974-01-11 1974-01-11 Apparatus including novel bridge circuit

Publications (1)

Publication Number Publication Date
US3964315A true US3964315A (en) 1976-06-22

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ID=23717547

Family Applications (1)

Application Number Title Priority Date Filing Date
US05/432,778 Expired - Lifetime US3964315A (en) 1974-01-11 1974-01-11 Apparatus including novel bridge circuit

Country Status (7)

Country Link
US (1) US3964315A (enrdf_load_stackoverflow)
JP (1) JPS50104066A (enrdf_load_stackoverflow)
CA (1) CA1010954A (enrdf_load_stackoverflow)
DE (1) DE2500805A1 (enrdf_load_stackoverflow)
FR (1) FR2257908B1 (enrdf_load_stackoverflow)
GB (1) GB1490261A (enrdf_load_stackoverflow)
IT (1) IT1024973B (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4096748A (en) * 1975-12-31 1978-06-27 Compagnie Internationale Pour L'informatique Cii-Honeywell Bull (Societe Anonyme) Wheatstone bridge measuring circuit
EP0393814A1 (en) * 1989-02-18 1990-10-24 Eaton Limited Temperature sensor for an electrical load resistor
US20090000093A1 (en) * 2007-06-26 2009-01-01 Headway Technologies, Inc. Capacitor and method of manufacturing the same and capacitor unit
RU2475763C1 (ru) * 2011-08-09 2013-02-20 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2499997C2 (ru) * 2012-02-28 2013-11-27 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2538946C1 (ru) * 2013-07-16 2015-01-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2537740C1 (ru) * 2013-06-06 2015-01-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
WO2015100422A1 (en) * 2013-12-27 2015-07-02 University Of Washington Through Its Center For Commercialization Adaptive control of a fiber scanner with piezoelectric sensing
RU2598977C1 (ru) * 2015-06-15 2016-10-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US964961A (en) * 1910-03-24 1910-07-19 Standard Underground Cable Company Cable construction.
US2612779A (en) * 1950-03-22 1952-10-07 Stewart F Mulford Compensated thermocouple
US2782102A (en) * 1954-08-31 1957-02-19 Foxboro Co Gas analyzer
US3226636A (en) * 1960-12-21 1965-12-28 Fenwal Inc Dual function circuit
US3296866A (en) * 1963-02-04 1967-01-10 Hitachi Ltd Electric thermometer
US3333476A (en) * 1962-11-13 1967-08-01 Lyons & Co Ltd J Temperature measuring apparatus
US3748655A (en) * 1966-09-20 1973-07-24 Anaconda Co Temperature monitored cable system with telemetry read-out

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US964961A (en) * 1910-03-24 1910-07-19 Standard Underground Cable Company Cable construction.
US2612779A (en) * 1950-03-22 1952-10-07 Stewart F Mulford Compensated thermocouple
US2782102A (en) * 1954-08-31 1957-02-19 Foxboro Co Gas analyzer
US3226636A (en) * 1960-12-21 1965-12-28 Fenwal Inc Dual function circuit
US3333476A (en) * 1962-11-13 1967-08-01 Lyons & Co Ltd J Temperature measuring apparatus
US3296866A (en) * 1963-02-04 1967-01-10 Hitachi Ltd Electric thermometer
US3748655A (en) * 1966-09-20 1973-07-24 Anaconda Co Temperature monitored cable system with telemetry read-out

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4096748A (en) * 1975-12-31 1978-06-27 Compagnie Internationale Pour L'informatique Cii-Honeywell Bull (Societe Anonyme) Wheatstone bridge measuring circuit
EP0393814A1 (en) * 1989-02-18 1990-10-24 Eaton Limited Temperature sensor for an electrical load resistor
US20090000093A1 (en) * 2007-06-26 2009-01-01 Headway Technologies, Inc. Capacitor and method of manufacturing the same and capacitor unit
US8085522B2 (en) * 2007-06-26 2011-12-27 Headway Technologies, Inc. Capacitor and method of manufacturing the same and capacitor unit
RU2475763C1 (ru) * 2011-08-09 2013-02-20 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2499997C2 (ru) * 2012-02-28 2013-11-27 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2537740C1 (ru) * 2013-06-06 2015-01-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
RU2538946C1 (ru) * 2013-07-16 2015-01-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников
WO2015100422A1 (en) * 2013-12-27 2015-07-02 University Of Washington Through Its Center For Commercialization Adaptive control of a fiber scanner with piezoelectric sensing
US9872606B2 (en) 2013-12-27 2018-01-23 University Of Washington Through Its Center For Commercialization Adaptive control of a fiber scanner with piezoelectric sensing
US10349818B2 (en) 2013-12-27 2019-07-16 University Of Washington Through Its Center For Commercialization Adaptive control of a fiber scanner with piezoelectric sensing
RU2598977C1 (ru) * 2015-06-15 2016-10-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Юго-Западный государственный университет" (ЮЗГУ) Мостовой измеритель параметров двухполюсников

Also Published As

Publication number Publication date
DE2500805A1 (de) 1975-07-17
CA1010954A (en) 1977-05-24
GB1490261A (en) 1977-10-26
FR2257908B1 (enrdf_load_stackoverflow) 1978-12-08
JPS50104066A (enrdf_load_stackoverflow) 1975-08-16
IT1024973B (it) 1978-07-20
FR2257908A1 (enrdf_load_stackoverflow) 1975-08-08

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Owner name: ANACONDA-ERICSSON INC., A CORP. OF DE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:ANACONDA COMPANY, THE A CORP. OF DE;REEL/FRAME:003846/0822

Effective date: 19800728

Owner name: ANACONDA-ERICSSON INC., A CORP. OF, DELAWARE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ANACONDA COMPANY, THE A CORP. OF DE;REEL/FRAME:003846/0822

Effective date: 19800728